Steerable, electrically powered, three wheeled vehicles of the type disclosed in the present assignee's U.S. Pat. No. 4,846,295, which is incorporated by reference herein for any necessary purpose, have employed electrically powered, swivelable, vertically adjustable post supported contour chairs which have been manually locked in position by hand operated levers. The locking occurred as a result of locking linkage going to an over center position. Various prior art patents, as set forth hereinafter, have provided safety switches and the like for the automatic deactivation of a motor vehicle. U.S. Pat. No. 4,795,865, for example, provides a switch under the seat which is closed when the operator is seated in the seat and permits the vehicle to be operated. In the event the operator steps from or is thrown from the seat, force applied to the actuator by a spring is sufficient to open the switch thereby deactivating the vehicle engine. U.S. Pat. No. 4,274,503 discloses a seat post which is moved upwardly and downwardly by an electric motor through the position of gearing and screw nut mechanism. Other prior art patents are as follows:
______________________________________ 3,500,946 Boyajian 4,274,503 Mackintosh 4,285,418 Paine 4,392,543 Buckhouse et al 4,392,544 Dilno 4,633,962 Cox et al 4,655,313 Hicks 4,795,865 Howard ______________________________________
The prior art patents identified herein, neither singularly nor combinatively, disclose the subject matter which is claimed.